My A100 was modifed by Precision Camera. They did an awesome job. Total cost to me was $264.99 which included shipping. I sent it to them on a Monday, USPS Express, and I had it back in hand the next Tuesday!
I'll post the contact info here.
Mark Soares (MSoares at precisioncamera.com)
Send Mark and email requesting the required form for an IR conversion and tell him Keith (aka groovyone) sent ya! (No, I do not get a referral) They did a great job with mine and Mark answered many annoying emails from me. I am very, very happy with the results, service and cost! The cost was $249 + S&H for APS-C and $299 + S&H for full frame. They do any brand (as far as I know) and since they are a major repair center, and one of Sony's warrenty repair centers, they have all the correct factory tooling to do the job.